1. Field of the Invention
The present invention relates to information processing apparatuses, and, more particularly, to an information processing apparatus and an information processing method for switching between a plurality of operation modes of different power consumptions in response to a request transmitted from an apparatus on a network and a program causing a computer to perform the information processing method.
2. Description of the Related Art
There is a technique called Wake on LAN (WOL) allowing a remote control apparatus to turn on a specific apparatus via a network. Magic Packet is a famous WOL technique developed by AMD (Advanced Micro Devices) Inc. In this WOL technique, for example, a WOL packet obtained by setting the MAC (Media Access Control) address of a target apparatus for a specific type of packet or a packet including specific data is transmitted. The target apparatus in a standby mode detects the WOL packet and is turned on. For example, such a technique is used to turn on a server connected to an intra-company LAN (Local Area Network).
As enhanced usage of WOL, for example, a case can be assumed in which a user away from the home turns on a home server via the Internet and makes a reservation of a program to be recorded. In this case, if the general setting of an in-home LAN is performed, a WOL packet transmitted via the Internet is discarded by a broadband router disposed at an entrance of a home server system. Therefore, it is necessary to perform a setting called port forwarding for the broadband router so as to convert a destination IP (Internet Protocol) address and a port number (on a WAN) included in the WOL packet transmitted via the Internet into a home server IP address and a home server port number (on a LAN), respectively. As a result, the broadband router can convert the destination IP address and the port number (on a WAN) included in the WOL packet into the home server IP address and the home server port number (on a LAN). However, in order to transfer the WOL packet to the home server, it is necessary to specify the MAC address of the home server that is the destination of the WOL packet. If the broadband router stores an ARP (Address Resolution Protocol) table in which an IP address and a MAC address are associated with each other, it acquires the MAC address of the home server that is the destination of the WOL packet using the ARP table and transfers the WOL packet. However, in general, such a broadband router periodically performs automatic updating of LAN setting so as to respond to changes in LAN configuration which are caused by, for example, the actuation or shutdown of an apparatus connected thereto. In the updating of LAN setting, the broadband router erases ARP table information after a predetermined period has elapsed. In this case, it is difficult for the broadband router to acquire the MAC address of the home server and transfer the WOL packet to the home server.
In this WOL technique, if the authentication of a packet to be transmitted to an apparatus via a network such as the Internet is not performed, a malicious user may turn on the apparatus. This compromises the security of the apparatus. A WOL technique that includes an authentication function as an additional function has been proposed. For example, a method of performing the authentication of an apparatus at the time of receiving a WOL packet from the apparatus and turning on a target apparatus only when the apparatus is authenticated is disclosed (see, for example, Japanese Unexamined Patent Application Publication No. 2005-062955 (FIG. 13) and U.S. Pat. No. 6,311,276 (FIG. 3)).